Configuration and operation of cross-domain services is a major issue for network and network-service providers. As service providers establish peering and wholesale relationships with multiple service provider partners, they find themselves in a complex situation in which services must be deployed across a constellation of different and non-integrated vendor, service, and technology-specific management systems. The problem of cross-domain service management, whether it means coordinating management operations across internal administrations, technologies, vendors, or with management systems of external providers is mainly caused by the ineffectual methods for exchanging network-service information between disparate domain management systems.
At the same time, the mix of technologies in telecommunications networks offers multiple implementation options for connecting end-users to the network and providing transport of service traffic. It becomes almost impossible for end-users and service providers to make effective implementation choices. For example, based on congestion, availability, or cost, an enterprise may decide to send data via a secure private tunnel over the Internet, or choose a managed IP VPN service from one or more Network Service Providers offering the same service with guaranteed Service Level Agreements (for example, Quality of Service, availability) and differentiated pricing. Similarly, a Network Access Provider might choose to establish multiple peering arrangements with Internet Service Providers to offer Internet Access Services to its access customers. In this environment, one needs to have adequate information to make an informed decision. However, a predetermined way to implement a service across the various network and network management domain administrations is not viable.
Currently, methods for integrating management systems are either based on deploying manual and static workflow procedures or building a costly, highly integrated and service-specific umbrella management system. The manual solution requires that the workflow procedures be coordinated across various vendor-specific domain managers using various Graphical User Interfaces. Service operators must manually exchange peering information and interconnection agreements about their respective networks as each domain manager is restricted to viewing and managing only the resources under its direct supervision. The integrated solution requires that the umbrella management system interfaces with all the involved domain management systems. However, integration of domain managers into an OSS system can lead to scalability problems, since a very large set of detailed management information from all domain managers must be maintained within a single system, while resources are micro-managed at the lowest level. An integrated solution may also be relatively inflexible, having limited adaptability to changes. An integrated solution also requires each service provider to give up some control over resources in its domain, which service providers may be reluctant to do as it would require exposing information to other domains.
Within the network layer, network elements have for many years adopted a distributed and collaborative inter-working approach based on the capability of exchanging reachability information on a peer-to-peer basis using dedicated advertisement mechanisms for specific services. The best example of such mechanisms is the Border Gateway Protocol 4 (BGPv4) that has proven to be very useful in large scale networks, namely the Internet. Nevertheless, some scalability and security problems have been identified with respect to BGPv4. Furthermore BGPv4, as a means to exchange reachability information, is technology specific in that it refers to addresses that are specific to a transport or networking technology. As a result, no end-to-end mechanism exists to support service routing convergence across those different networks.
A distributed mechanism for exchanging service reachability information across domains of different technologies or administrations would permit routing of cross-domain services, without requiring a costly and inflexible umbrella management system.